The primary danger to a person located in a burning house or other building is smoke inhalation. Smoke given off from a fire can quickly engulf the air within a burning building. Persons in high-rise office and apartment buildings are particularly susceptible to the dangers of smoke inhalation. Due to the length of time often required to exit such a building, the probability of being overcome by smoke is more likely.
To prevent smoke inhalation and to provide people trapped in a burning building a chance to exit the building, smoke masks must be provided. Smoke masks filter the smoky, contaminated air and allow a person sufficient time to exit the building. Each person in a building, particularly those persons located in areas that require additional time to exit the building, should have a smoke mask at their disposal in case of fire. In order for it to be economically feasible to supply a gas mask for each person located in a building, the gas mask should be disposable and relatively inexpensive.
Disposable gas mask intended for general use by a person who may be trapped in a burning building are known and have been commercially available. Typically, prior art disposable gas masks have a rubber-type main body that forms a hood sized to fit over the head. The mask must be stretched and pulled over the user's head so that the mask clings to the user's face and head. The mask is designed to cling about the person's head to prevent contaminated air from passing by the gas mask and exposing the wearer to the contaminated air. A filter for filtering the smoky, contaminated air is typically located on a front portion of the gas mask and provides an uncontaminated or clean supply of air to the wearer.
There are several problems with prior art disposable gas masks. One primary problem is that the gas mask must be stretched to fit over the head of a wearer and then clings to the head and face of the wearer. Many users have a natural apprehension about pulling such a tight-fitting mask over their heads and about their face. In addition, such a mask is uncomfortable and difficult to position on the person's head. In addition, it is very difficult for a person to pull this type of smoke mask over his or her face when that person wears prescription glasses. For a person wearing prescription glasses, the requirement of pulling such a smoke mask over his or her head can only increase the natural apprehension. Finally, the very nature of the stretchable, skin-tight smoke mask of the prior art does not lend itself to creating an effective seal for a wide variety of people having various size heads.
The filters used on prior art disposable gas masks also have problems. The filters of the prior art are not very effective at removing all of the contaminants, especially gas, from the smoky air and also only protect the user from the contaminated air for a limited period of time. Filters of the prior art typically include an outer particulate layer and an activated carbon layer. The particulate layer removes particulate matter from the contaminated air while the carbon layer absorbs gaseous contaminants from the contaminated air. Generally, the carbon-activated layer is formed from a carbon-saturated material. Carbon-saturated filter material is typically effective for only a relatively short time when in use. Thus, filters used in prior smoke masks are not really designed for longevity.